phpList is an open-source newsletter manager. phplist is free to download, install and use, and is easy to integrate with any website. phplist is downloaded more than 10000 times per month.Version : 3.3.7Release Date : 14-12-2018

poMMo is versatile mass mailing software. It can be used to add a mailing list to your Web site or to organize stand alone mailings. Unique Features such as the ability to mail subsets of your subscribers set it apart from alternatives.
Version : 16.1Release Date : 02-04-2008

SquirrelMail is a standards-based webmail package written in PHP. It includes built-in pure PHP support for the IMAP and SMTP protocols, and all pages render in pure HTML 4.0 for maximum compatibility across browsers. SquirrelMail has all the functionality like email client, including strong MIME support, address books, and folder manipulation.Version : 1.4.22Release Date : 12-07-2011

RainLoop webmail Simple, modern & fast web-based email client.
RainLoop webmail was designed with efficient memory use in mind, so it can work fine even on low-end web servers.
Regardless of mailbox size and number of mails in it, memory use per active user is always kept at a minimum, even when very large mails are processed. Version : 1.12.1Release Date : 31-07-2018

WEBinsta maillist manager is built to provide a centralized mailing list / newsletter system for small to medium website . Its simple yet quite powerfull . It support the standard subscribe and un-subscribe , remote verification , unsubscribe links , attachments and host of other such features . The best of all the total integration is less than 3 lines of code .Version : 1.3e

OpenNewsletter is a web-based open source solution for sending email newsletters to a subscriber list. Email delivery options include an HTML version and/or a Text version.Version : 2.5.1Release Date : 22-07-2016

CcMail is a free, open, powerful Mailing List Manager that doesnt require any programming knowledge. It was designed to have a user-friendly interface, being in the same time complete and powerful. CcMail offers the basic functionalities of a commercial, expensive script for free.Version : 1.0.2